to compare the predictive accuracy of regression models for a non-consecutive day VO2max/Wingate testing protocol and a same day testing protocol. Participants (N=23) completed a treadmill GXT and Wingate cycle test. Participants (n=12) completed testing on non-consecutive days (NON) and (n=11) the same day (SAME). VO2max (L/min) and peak power (PP) were collected. Linear regression analysis of NON revealed R2=0.808 and prediction equation ?=1.499+0.004X and SAME showed R2=0.861 and prediction equation ?=1.407+0.003X. NON standard error of estimate (SEE) and standard error of estimate percent (SEE %) were 0.62 L/min and 15.23%, respectively. SAME SEE and SEE% were 0.34 L/min and 10.98%, respectively. These results indicate PP obtained the same day of VO2max testing is a better predictor of cardiorespiratory fitness. Similarly, the SAME model is more accurate according to SEE and SEE%. This may be due to diminished effects of training adaptations that could occur 2-7 days between testing sessions during the NON testing protocol in healthy, active young adults.